1. Combine sour cream, Dijon, whole grain mustard, garlic, and thyme in a small bowl. Mix well. Pour mixture in a baking dish that can fit inside your Air Fryer basket.
2. Add the drumsticks and turn to coat all sides. Season with salt and pepper to taste.
3. Preheat your Air Fryer to 380 F (190 C).
4. Cook the chicken 25-30 minutes or until chicken is cooked through, turning halfway through cooking time. Garnish with thyme sprig if desired.